DE102021102803B4 - Device and method for converting low-temperature heat into technically usable energy - Google Patents

Abstract

Energy converter (21) for the isentropic conversion of the thermal energy of a liquid working medium (52) under pressure and heated by contact with a heat source into potential energy by realising a partial flash evaporation according to the TLC2 process, characterised by at least the following components:
• A closed, thermally insulated, upward pipe system with an ascent pipe (130) and a descent pipe (160), connected by pipe bends (110, 140)
• A number of at least 10 pistons (170) rotating freely in the closed pipe system
• The tubes for guiding the pistons (170) are provided with a good sliding thermal internal insulation such as PTFE or polyamide (PA)
• The pistons (170) are provided with a sealing and sliding material on the sealing surfaces that matches the material of the inner insulation of the pipe, which ensures both sealing of the areas and thermal insulation
• Introduction openings and an introduction device (121) at the lower level of the pipe system for introducing a working medium (52) heated by contact with a heat source into a working area (AB) between two pistons (170)
• Outlet openings in the casing of the pipe at the upper level for discharging the remaining liquid (51) and the vaporized (54) working fluid from the pipe system
• A separation device (150) for separating the evaporated working medium (54) from the liquid, cold working medium (51).

Description

The invention relates to devices and methods for converting low-temperature heat with a maximum temperature of 200°C into technically usable mechanical energy and subsequently electrical energy.

State of the art

Due to the small temperature difference between low-temperature heat sources and possible heat sinks such as water or ambient air and the resulting low theoretical efficiency, it is desirable to utilize as much of the theoretically usable thermal energy as possible. This is made possible by implementing a trilateral cycle (TLC) process according to Smith ( US$4,557,112 ), which theoretically has the highest exergetic efficiency compared to other thermal power processes such as a steam power process or ORC process.

• - Isochore Druckerhöhung (Pkt. 1 - Pkt. 2)
• - Isobare Wärmezufuhr ohne Verdampfung des Arbeitsmittels (Pkt. 2 - Pkt. 3)
• - Isentrope Entspannungsverdampfung bei kontinuierlicher Druckverringerung mit gleichzeitiger Volumenvergrößerung und Verrichten von Volumenarbeit (Pkt. 3 - Pkt. 5)
• - Isobare Wärmeabfuhr und Kondensation des verdampften Anteils des Arbeitsmittels (Pkt. 5 - Pkt. 1)

In the TLC process according to Smith (see 1 ) a tool goes through the following steps:

• - Isochoric pressure increase (point 1 - point 2)
• - Isobaric heat supply without evaporation of the working fluid (point 2 - point 3)
• - Isentropic flash evaporation with continuous pressure reduction with simultaneous volume increase and performance of volume work (points 3 - 5)
• - Isobaric heat removal and condensation of the evaporated portion of the working fluid (point 5 - point 1)

The basic structure of a device according to the state of the art is shown in 2 shown. Starting at point 1, a working medium is put under working pressure by a pressure pump, external heat is added in a heat exchanger, this is converted into a rotational movement by partial evaporation of the working medium in a heat engine, which drives a generator. The resulting working medium vapor is condensed after leaving the heat engine and the cycle begins again.

The technical challenge of the TLC process lies in the implementation of the partial evaporation as forced flash evaporation with a vertically falling evaporation curve (see 1 , TS diagram, progression from point 3 to point 5) through the wet vapor region of the working fluid with a high proportion of liquid.

• • Reduktion des Arbeitsdruckes zur Initiierung der Entspannungsverdampfung des Arbeitsmittels
• • Volumenvergrößerung durch die Entspannungsverdampfung des Arbeitsmittels
• • Verrichten von Expansionsarbeit durch den entstehenden Dampf des Arbeitsmittel
• • im Nassdampfgebiet des Arbeitsmittels mit einem hohen Flüssigkeitsanteil

stellt hohe technische Anforderungen an die verwendete Vorrichtung.The continuous, simultaneous and spatial coexistence of:

• • Reduction of the working pressure to initiate the flash evaporation of the working fluid
• • Volume increase due to the flash evaporation of the working fluid
• • Carrying out expansion work through the steam generated by the working medium
• • in the wet steam area of the working fluid with a high liquid content

places high technical demands on the device used.

• • US 3 169 375 A benennt Rotationsmaschinen
• • US 4 557 112 A benennt Screw- und Vaneexpander
• • US 7 093 503 B1 und DE 10 2007 041 457 A1 nennen Turbinensysteme
• • WO 2007/ 115 769 A2 verweist auf Kolbenmaschinen

Various devices are known for implementing the flash evaporation of a TLC process:

• • US 3 169 375 A names rotary machines
• • US 4 557 112 A names screw and vane expanders
• • US 7 093 503 B1 and EN 10 2007 041 457 A1 call turbine systems
• • WO 2007/ 115 769 A2 refers to piston engines

The technical literature also refers to scroll expanders and other variants of rotary vane expanders as expansion machines.

These devices were mostly developed as compression machines for the compression of gases or derived from machines for other thermal power processes and sometimes have unfavorable parameters for flash evaporation according to the TLC process.

• • Die p-V-Kennlinie der Vorrichtung entspricht nicht oder nur ungenügend der p-V-Verdampfungskennlinie des Arbeitsmittels, was zu Umwandlungsverlusten führt
• • Ein zu geringes Expansionsverhältnis von Volumen und Druck und dadurch kein vollständiges Durchlaufen der Verdampfungskurve, was zu ungenutzter thermischer Energie führt
• • hohe Spalt-Verluste an technisch bedingten Dichtflächen bei durch höhere Temperaturen bedingten höheren Arbeitsdrücken
• • Schlechte Anpassung der Vorrichtung an Veränderungen der Eingangstemperatur bzw. der Kondensationstemperatur aufgrund mechanisch vorgegebener Arbeitspunkte
• • Reibungsverluste
• • Z.T. hohe Drehzahlen der Vorrichtung, die zusätzliche, verlustbehaftete Getriebe erfordern
• • Aufwendig und teuer zu fertigende Spezialkomponenten (wie u.a. Turbinen, Screw-Expander)
• • Bauteilschäden durch Tröpfchenerosion, ausgelöst durch eine schnelle, schlagartige Entspannungsverdampfung

This includes:

• • The pV characteristic of the device does not correspond or only insufficiently corresponds to the pV evaporation characteristic of the working medium, which leads to conversion losses
• • An expansion ratio of volume and pressure that is too low and therefore the evaporation curve is not completed, which leads to unused thermal energy
• • high gap losses on technically conditioned sealing surfaces at higher working pressures caused by higher temperatures
• • Poor adaptation of the device to changes in the inlet temperature or the condensation temperature due to mechanically predetermined operating points
• • Friction losses
• • ZT high speeds of the device, which require additional, lossy gears
• • Special components that are complex and expensive to manufacture (such as turbines, screw expanders)
• • Component damage due to droplet erosion, triggered by rapid, sudden flash evaporation

Another point that is often emphasized in the scientific literature is the necessary pumping power to generate the required working pressure for the cold liquid working medium at the beginning of the process, which requires a significant portion of the previously generated energy.

• • US 6 412 281 B2
• • DE102018130412A1
• • DE 40 35 870 A1
• • DE 29 43 686 A1
• • US 4 187 686 A
• • US 3 953 971 A

Various devices with pipe systems for converting thermal energy into technically usable energy are also known:

• • US 6 412 281 B2
• • DE102018130412A1
• • DE 40 35 870 A1
• • DE 29 43 686 A1
• • US 4 187 686 A
• • US 3 953 971 A

Object of the invention

• • die p-V-Kennlinie der Vorrichtung entspricht der p-V-Verdampfungskennlinie des Arbeitsmittels
• • Ein großes volumenbezogenes Expansionsverhältnis
• • Ein großes druckbezogenes Expansionsverhältnis
• • geringe Spaltverluste an technisch bedingten Dichtflächen
• • Vermeidung einer schlagartigen Entspannungsverdampfung und dadurch ausgelöster Tröpfchenerosion
• • Minimierung der zur Erzeugung des Arbeitsdruckes erforderlichen Pumpleistung
• • Leichte Anpassung an Veränderungen der thermischen Umgebungsparameter wie Temperatur der Wärmequelle bzw. der Kondensationstemperatur
• • Abdeckung eines großen Temperaturbereichs der Temperatur der NiedertemperaturWärmequelle und der Kondensationstemperatur

The aim of the present invention is a technical solution for converting low-temperature heat into technically usable energy by realizing flash evaporation according to the TLC process ( 1 ) while eliminating the disadvantages of the previously known devices.
This means that the new technical solution should have the following properties:

• • the pV characteristic of the device corresponds to the pV evaporation characteristic of the working fluid
• • A large volume-related expansion ratio
• • A large pressure-related expansion ratio
• • low gap losses on technically conditioned sealing surfaces
• • Avoidance of sudden flash evaporation and the resulting droplet erosion
• • Minimization of the pumping power required to generate the working pressure
• • Easy adaptation to changes in the thermal environment parameters such as temperature of the heat source or the condensation temperature
• • Coverage of a wide temperature range of the low temperature heat source temperature and the condensation temperature

Explanation of the solution approach

• • Erste Wandlung: Umwandlung der thermischen Energie eines Arbeitsmittels in potentielle Energie des Arbeitsmittels durch Anheben des Arbeitsmittels von einem unteren Niveau auf ein oberes Niveau unter Realisierung einer Entspannungsverdampfung nach dem TLC-Prozess
• • Zweite Wandlung: Umwandlung der potentiellen Energie des Arbeitsmittels in technisch nutzbare Energie durch Rückführung des Arbeitsmittels vom oberen auf das untere Niveau und Umwandlung des statischen Druckes des Arbeitsmittels in mechanische Energie, z.B. in einem Hydraulikmotor / -turbine

The object is achieved according to the invention as defined in the claims by an energy conversion device and a method for converting thermal energy into potential energy as well as a device and method with a two-fold energy conversion:

• • First conversion: Conversion of the thermal energy of a working medium into potential energy of the working medium by raising the working medium from a lower level to an upper level by realizing flash evaporation according to the TLC process
• • Second conversion: Conversion of the potential energy of the working medium into technically usable energy by returning the working medium from the upper to the lower level and converting the static pressure of the working medium into mechanical energy, e.g. in a hydraulic motor / turbine

• • Die erste Energiewandlungsvorrichtung und das Verfahren zur Wandlung von thermischer Energie in potentielle Energie unter Realisierung einer Entspannungsverdampfung nach dem TLC-Prozess
• • Die Vorrichtung und das Verfahren der zweimaligen Wandlung unter Verwendung der neuartigen ersten Energiewandlungsvorrichtung

New are:

• • The first energy conversion device and method for converting thermal energy into potential energy by realizing flash evaporation according to the TLC process
• • The device and method of double conversion using the novel first energy conversion device

For better differentiation, the first energy conversion device is hereinafter referred to as “First Energy Converter”.

The device with two-fold energy conversion is hereinafter referred to as the "overall system". The thermodynamic process with two-fold energy conversion realized in the overall system is hereinafter referred to as the "TLC2 process" due to its similarity to the known TLC process and to better distinguish it from the state of the art.

In the 1 The reference symbols used in the TLC process are used identically in the TLC2 process.

Complete system with two energy conversions

Core component of the overall system 11 according to 4 is the first energy converter 21.

In 3 the thermodynamic details of the TLC2 process for the entire system 11 as well as the corresponding TS and pV diagram are shown.

The working fluid under pressure at point 2 is heated in a heat exchanger 31 by externally supplied thermal energy and fed to the first energy converter 21.

In the first energy converter 21 for converting thermal energy into potential energy, the step of flash evaporation (see 3 , TS diagram) from operating point 3 with the maximum temperature to operating point 5 with the minimum temperature. This achieves a maximum in exergetic efficiency.

The working fluid raised by the first energy converter 21 and partially evaporated is collected after leaving the first energy converter 21, the working fluid vapor 54 condenses, is collected together with the working fluid 51 that has remained liquid and is returned to the lower level by performing mechanical work in a second energy converter 34. In contrast to the original TLC process according to 1 In the TLC2 process, between the thermodynamic points 1 and 2, there is another point 7 at which the cold working fluid 51 has a higher pressure than is required at point 2 according to the TLC2 process.

This pressure difference between points 7 and 2 of the TLC2 process is converted into technically usable energy in the second energy converter 34. At the same time, the pump required according to the state of the art to generate the necessary working pressure is no longer required.

The product of the pressure difference and the volume of the working fluid corresponds to the thermal energy converted into potential energy in the first energy converter 21.

The first energy converter

The physical and technical basis for the first energy converter 21 (see 5a) are working areas AB each delimited by two pistons 170 and filled with warm working fluid AM. A large number of these working areas separated by pistons 170 are arranged one above the other in an upwardly directed tube (see 5b) .

Each working area is subject to a local working pressure pA, which is generated by the other working areas located in the pipe above the respective working area.

Depending on the number of additional working areas located above a single working area and the local working pressure pA prevailing in a single working area, the working medium AM has partially evaporated in a flash evaporation with a simultaneous increase in volume and has cooled down through the flash evaporation (see 5b) .

The increase in volume raises all work areas above it.

By adding new work areas (see 5b) At the lower level of the upwardly directed pipe, the work areas above are raised to such an extent that the uppermost work area at the upper level emerges from the upwardly directed pipe.

This reduces the local working pressure pA for all subsequent working areas.

This reduction in pressure leads to small flash evaporations in all working areas in the pipe and thus small increases in volume of each individual working area and consequently a lifting of all working areas above.

The sum of these many small volume increases results in a large volume increase, which greatly increases the upper working area (see 5b - resulting path change) and - after adding a new working area at the lower level - exits at the upper level.

In order to ensure that this process is repeated continuously, new working areas with warm working fluid are constantly supplied to the lower level under a dosing pressure pD.

Further development of the first energy converter

This in 5 The principle of the first energy converter outlined requires a greater height of the upwardly directed pipe - to build up the maximum working pressure pA which increases with temperature - the greater the temperature difference between the low-temperature heat source and the vapor condensation temperature (given by the temperature of the heat sink).

This may require heights of several hundred meters to over 1000 meters.

This can be achieved according to an advantageous further development of the first energy converter (see 6a -b) can be avoided by inserting an additional weight area GB filled with a weight medium 60 between two working areas AB (see 6a) .

In contrast to the working fluid, the weight medium is not heated by the heat source. In terms of their composition, the working fluid and the weight medium can - but do not have to - be identical, i.e. unheated working fluid is used as the weight medium.

The weight medium causes - with otherwise identical processes as in 5 As described above, it increases the working pressure on every working area AB in the upward pipe due to its own weight. This makes it possible - as will be shown later - to significantly reduce the height of the upward pipe required to build up the working pressure pA.

The 7 The structure of the overall system 12 with a further developed first energy converter 22 is largely identical to the overall system 11 according to 4 .

What is new is the supply of weight medium to the further developed first energy converter 22.

The thermodynamic processes of the TLC2 process according to 3 also apply to the overall system 12 with the further developed first energy converter 22.

The pressure difference between points 7 and 2, which is reduced due to the lower height of the overall system 12, is compensated for by a larger volume of working fluid and weight medium for the second energy converter (see 7 , pV diagram).

By varying the amount of working fluid or weight medium, the entire system can be easily controlled. A particular advantage is that the further developed first energy converter can also be operated in an operating mode without weight medium, thus extending the usable temperature range to lower temperatures and temperature differences.

Increased performance through parallelization

The principle and the simple technology of the first energy converter and the further developed first energy converter for converting thermal energy into potential energy allows any number of upward-leading pipes for energy conversion to be built in parallel (see 8th ).

This has the advantage that even with small temperature differences between the low-temperature source and the steam condensation temperature and the associated low efficiency, large amounts of heat can still be converted and technically usable energy can be obtained from it.

With parallelization, outputs well into the megawatt range can be achieved.

• • Erfolgt durch das Prinzip der frei beweglichen Kolben eine selbsttätige Anpassung der p-V-Kennlinie der ersten Energiewandler an die p-V-Verdampfungskennlinie des Arbeitsmittels
• • Ist eine stufenlose Volumenvergrößerung von mehr als 1:100 möglich (Ausgangsvolumen des flüssigen warmen Arbeitsmittels zu Endvolumen des teilverdampften gasförmigen/flüssigen kalten Arbeitsmittels)
• • ist eine stufenlose Druckentspannung von mehr als 1:10 möglich (maximaler Arbeitsdruck auf dem unteren Niveau zu minimalem Arbeitsdruck auf dem oberen Niveau)
• • Wird durch einen sehr langsamen Druckabbau von mehreren Sekunden bis Minuten (Zeit zwischen Beginn und Ende der Entspannungsverdampfung des Arbeitsmittels) eine explosionsartige Verdampfung des Arbeitsmittels und nachfolgende Tröpfchenerosion, die zu Bauteilzerstörungen führen kann, vermieden
• • Werden durch geringe Druckunterschiede von weit weniger als 0,001 MPa (0,01 bar) zwischen der Kolbenoberseite und der Kolbenunterseite die technischen Anforderungen an die Kolbendichtungen deutlich gesenkt und Spaltverluste weitestgehend reduziert
• • Sind durch mehrere parallel arbeitende erste Energiewandler Leistungen bis weit in den Megawatt-Bereich möglich
• • Ist durch Änderung der zugeführten Mengen des Arbeitsmittels, des Gewichtsmediums oder der Betriebsweise im weiterentwickelten ersten Energiewandler eine einfache Anpassung des TLC2-Prozesses an Veränderungen der externen Temperatur der Niedertemperaturwärmequelle und/oder der Temperatur der Dampfverflüssigung möglich
• • können bereits geringe Temperaturdifferenzen von 10°K zur Energiegewinnung ausgenutzt werden
• • ist ein flexibler Tag/Nacht-Betrieb sowie ein flexibler Sommer/Winter-Betrieb mit Anpassung an die sich verändernden Temperaturen der Niedertemperaturwärmequelle oder der Dampfverflüssigungstemperatur möglich

By using the first energy converter according to the invention, the further developed first energy converter according to the invention and the parallelization of the first and the further developed first energy converter:

• • The principle of freely moving pistons results in an automatic adjustment of the pV characteristic of the first energy converter to the pV evaporation characteristic of the working medium
• • Is a continuous volume increase of more than 1:100 possible (initial volume of the liquid warm working medium to final volume of the partially evaporated gaseous/liquid cold working medium)
• • a continuous pressure relief of more than 1:10 is possible (maximum working pressure at the lower level to minimum working pressure at the upper level)
• • Explosive evaporation of the working fluid and subsequent droplet erosion, which can lead to component damage, is avoided by a very slow pressure reduction of several seconds to minutes (time between the start and end of the flash evaporation of the working fluid)
• • The technical requirements for the piston seals are significantly reduced and gap losses are reduced as a result of small pressure differences of far less than 0.001 MPa (0.01 bar) between the top and bottom of the piston
• • By using several energy converters working in parallel, outputs well into the megawatt range are possible
• • By changing the quantities of working fluid, weight medium or operating mode in the further developed first energy converter, it is possible to easily adapt the TLC2 process to changes in the external temperature of the low-temperature heat source and/or the temperature of the steam liquefaction
• • Even small temperature differences of 10°K can be used to generate energy
• • Flexible day/night operation and flexible summer/winter operation with adaptation to the changing temperatures of the low-temperature heat source or the steam condensation temperature is possible

• • die thermodynamisch anspruchsvollen Vorgänge der Wandlung der thermischen Energie nach dem TLC-Prozess in eine andere Energieform werden von der Wandlung in technisch nutzbare mechanische Energie entkoppelt (vergleichbar der Trennung von Dampferzeugung und Turbine in klassischen Wärmekraftwerken)
• • die technische Komplexität einer Vorrichtung zur Umwandlung thermischer Energie in technisch nutzbare Energie wird im Vergleich zum Stand der Technik deutlich reduziert, da jeder der beiden Energiewandler für seine jeweilige Aufgabe optimiert werden kann
• • Der zu Prozessbeginn erforderliche Arbeitsdruck für das Arbeitsmittel und ggf. des Gewichtsmediums wird verfahrens- und vorrichtungsintern ohne die nach dem Stand der Technik erforderliche Druckpumpe erzeugt
• • dies senkt die technisch bedingten Verluste, erhöht den technischen Wirkungsgrad des Gesamtsystems und bringt ökonomische Vorteile

The advantages of the two-stage process according to the invention for converting thermal energy into technically usable energy according to the TLC2 process are:

• • the thermodynamically demanding processes of converting thermal energy into another form of energy after the TLC process are distinguished from the conversion into technically usable mechanical Energy decoupled (comparable to the separation of steam generation and turbine in conventional thermal power plants)
• • the technical complexity of a device for converting thermal energy into technically usable energy is significantly reduced compared to the state of the art, since each of the two energy converters can be optimized for its respective task
• • The working pressure required at the start of the process for the working medium and, if applicable, the weight medium is generated internally within the process and device without the pressure pump required according to the state of the art
• • This reduces technical losses, increases the technical efficiency of the overall system and brings economic benefits

List of illustrations

• 1 - Thermodynamics of the state-of-the-art TLC process
• 2 - Principle design of a system for using the state-of-the-art TLC process
• 3 - Thermodynamics of the modified TLC2 overall process
• 4 - Representation of the entire system 11 after the TLC2 process
• 5 - Functional principle of the first energy converter
• 6 - Functional principle of further developed first energy converter
• 7 - Representation of the entire system 12 after the TLC2 process
• 8th - Representation of the entire system 11 with several parallel first energy converters 21
• 9 - Thermodynamics of the modified M-TLC2 process
• 10 - Representation of overall system 13 after the M-TLC2 process
• 11 - Representation of the entire system 14 according to the M-TLC2 process
• 12 - Description of the structure and function of the first energy converter 21
• 13 - Description of the structure and function of the first advanced energy converter 22
• 14 - Representation of the variation of possible operating states of the first energy converters 21 and 22 in the TS diagram
• 15 - Representation of possible design variants of the pipe system of the first energy converters 21 and 22 at the lower and upper levels respectively

List of reference symbols and abbreviations used

Reference symbols

AB

Arbeitsbereich

AM

Arbeitsmittel

GB

Gewichtsbereich

GM

Gewichtsmedium

H

Fallhöhe Arbeitsmittel

pA

Arbeitsdruck

pD

Dosierdruck

pK

Kolbendruck

Ziffern 1 - 7 --- Prozesstechnische Punkte

• • Punkte bestimmter thermodynamischer und technischer Zustände in T-S und p-V Diagrammen

Ziffern 10 - 99 --- Gesamtsystem

11

Gesamtsystem zur Wandlung von Wärmeenergie in technisch nutzbare Energie

12

Weiterentwickeltes Gesamtsystem zur Wandlung von Wärmeenergie in technisch nutzbare Energie

21

Erster Energiewandler zur Wandlung von Wärmeenergie in potenzielle Energie

22

Weiterentwickelter erster Energiewandler zur Wandlung von Wärmeenergie in potentielle Energie

31

Wärmetauscher Niedertemperaturwärmequelle

32

Dampfverflüssigungsvorrichtung

33

Sammel- und Pufferbehälter

34

Zweiter Energiewandler, potentielle in technisch nutzbare Energie

40

Zuführungen, allgemein

41

Zuführung Gewichtsmedium

42

Zuführungen zum Druckaufbau

51

Arbeitsmittel, flüssig, kalt

52

Arbeitsmittel, flüssig, warm

53

Arbeitsmittel, dampfförmig, warm

54

Arbeitsmittel, dampfförmig, kalt

60

Gewichtsmedium (z.B. als flüssiges kaltes Arbeitsmittel)

Ziffern 100 - 199 --- Erster und weiterentwickelter erster Energiewandler

110

Rohrbogen, unteres Niveau

120

Einbringvorrichtung

121

Einbringvorrichtung, nur Arbeitsmittel

122

Einbringvorrichtung, Arbeitsmittel und Gewichtsmedium

125

Kolben-Stoppvorrichtung

126

Dosiervorrichtung

130

Aufstiegsrohr

140

Rohrbogen, oberes Niveau

150

Separierungsvorrichtung

160

Abstiegsrohr

170

Kolben

171

Kolbenstapel

AWAY

Workspace

AT THE

Work equipment

GB

Weight range

GM

Weight medium

H

Fall height of work equipment

pA

Working pressure

pD

Dosing pressure

pK

Piston pressure

Numbers 1 - 7 --- Process-related points

• • Points of certain thermodynamic and technical states in TS and pV diagrams

Numbers 10 - 99 --- Total system

11

Complete system for converting thermal energy into technically usable energy

12

Advanced overall system for converting thermal energy into technically usable energy

21

First energy converter to convert heat energy into potential energy

22

Advanced first energy converter for converting heat energy into potential energy

31

Heat exchanger low temperature heat source

32

Steam condensing device

33

Collection and buffer tanks

34

Second energy converter, potential into technically usable energy

40

Feeders, general

41

Feeding weight medium

42

Supply lines for pressure build-up

51

Working fluid, liquid, cold

52

Working fluid, liquid, warm

53

Working fluid, vaporous, warm

54

Working fluid, vaporous, cold

60

Weight medium (e.g. as liquid cold working medium)

Numbers 100 - 199 --- First and further developed first energy converter

110

Pipe bend, lower level

120

Insertion device

121

Insertion device, working equipment only

122

Feeding device, working equipment and weight medium

125

Piston stop device

126

Dosing device

130

Riser tube

140

Pipe bend, upper level

150

Separation device

160

Descent tube

170

Pistons

171

Piston stack

Detailed description of the process and the overall systems for converting thermal energy into technically usable energy

The following description describes the operation of the entire system 11 ( 4 ) and the further developed overall system 12 ( 7 ) together.

Differences are discussed in the text. The description of the thermodynamic steps follows the course of the TLC2 process according to 3 .

For a better understanding, the 4 and 7 the TS diagram and the pV diagram of the respective overall process are shown. The hatched area in the pV diagram corresponds to the thermal energy converted into technically usable work and is the same size for both devices with the same input parameters.

• • Einen Wärmetauscher 31 zur Übertragung der thermischen Energie einer Niedertemperaturwärmequelle an ein unter Druck stehendes flüssiges Arbeitsmittel 51 ohne Verdampfung des Arbeitsmittels
• • Thermisch isolierte Zuführungen 40, um das erwärmte Arbeitsmittel 52 einem ersten Energiewandler 21 zuzuführen
• • Mindestens ein erfindungsgemäßer erster Energiewandler 21 zur Umwandlung der thermischen Energie des Arbeitsmittels 52 unter Realisierung der Entspannungsverdampfung nach dem TLC2-Prozess in potentielle Energie
• • Zuführungen 40, um den entstandenen Arbeitsmitteldampf 54 einer Dampfverflüssigungsvorrichtung 32 zuzuführen
• • Eine Dampfverflüssigungsvorrichtung 32 zur Verflüssigung des verdampften Arbeitsmittels 54
• • Zuführungen 40, um das im ersten Energiewandler 21 flüssig gebliebene Arbeitsmittel 51 und das in der Dampfverflüssigungsvorrichtung 32 wieder verflüssigte Arbeitsmittel einem Sammelbehälter 33 zuzuführen
• • Ein Sammel- und Pufferbehälter 33 zur Zusammenführung des flüssig gebliebenen und des in der Dampfverflüssigungsvorrichtung 32 verflüssigten Arbeitsmittels
• • Zuführungen 42, um das flüssige, kalte Arbeitsmittel 51 unter Druckaufbau vom Sammelbehälter 33 einem zweiten Energiewandler 34 zuzuführen
• • Mindestens einen zweiten Energiewandler 34 zur Umwandlung der potentiellen Energie des Arbeitsmittels 51 in technisch nutzbare Energie
• • Zuführungen 40, um das noch unter Dosierdruck pD stehende Arbeitsmittel 51 vom zweiten Energiewandler 34 wieder dem Wärmetauscher 31 zuzuführen

The overall system 11 according to the invention ( 4 ) for the conversion of thermal energy into technically usable energy comprises at least the following components:

• • A heat exchanger 31 for transferring the thermal energy of a low-temperature heat source to a pressurized liquid working medium 51 without evaporation of the working medium
• • Thermally insulated feeders 40 to feed the heated working fluid 52 to a first energy converter 21
• • At least one first energy converter 21 according to the invention for converting the thermal energy of the working medium 52 into potential energy by realizing the flash evaporation according to the TLC2 process
• • Feeds 40 to feed the resulting working fluid vapor 54 to a vapor liquefaction device 32
• • A vapor liquefaction device 32 for liquefying the vaporized working fluid 54
• • Feeds 40 to feed the working fluid 51 remaining liquid in the first energy converter 21 and the working fluid liquefied again in the steam liquefaction device 32 to a collecting container 33
• • A collection and buffer tank 33 for combining the working fluid that has remained liquid and that liquefied in the steam liquefaction device 32
• • Feeds 42 to feed the liquid, cold working medium 51 under pressure from the collecting container 33 to a second energy converter 34
• • At least one second energy converter 34 for converting the potential energy of the working medium 51 into technically usable energy
• • Feeds 40 to feed the working medium 51, still under dosing pressure pD, from the second energy converter 34 back to the heat exchanger 31

• • Einen Wärmetauscher 31 zur Übertragung der thermischen Energie einer Niedertemperaturwärmequelle an ein unter Druck stehendes flüssiges Arbeitsmittel 51 ohne Verdampfung des Arbeitsmittels
• • Thermisch isolierte Zuführungen 40, um das erwärmte Arbeitsmittel 52 einem weiterentwickelten ersten Energiewandler 22 zuzuführen
• • Mindestens ein erfindungsgemäß weiterentwickelter erster Energiewandler 22 zur Umwandlung der thermischen Energie des Arbeitsmittels 52 unter Realisierung der Entspannungsverdampfung nach dem TLC2-Prozess in potentielle Energie
• • Zuführungen 40, um den entstandenen Arbeitsmitteldampf 54 einer Dampfverflüssigungsvorrichtung 32 zuzuführen
• • Eine Dampfverflüssigungsvorrichtung 32 zur Verflüssigung des verdampften Arbeitsmittels 54
• • Zuführungen 40, um das im ersten Energiewandler 22 flüssig gebliebene Arbeitsmittel 51, das Gewichtsmedium 60 und das in der Dampfverflüssigungsvorrichtung 32 wieder verflüssigte Arbeitsmittel 51 einem Sammelbehälter zuzuführen
• • Ein Sammel- und Pufferbehälter 33 zur Zusammenführung des flüssig gebliebenen, des in der Dampfverflüssigungsvorrichtung 32 verflüssigten Arbeitsmittels sowie des Gewichtsmediums
• • Zuführungen 42, um das flüssige, kalte Arbeitsmittel unter Druckaufbau vom Sammelbehälter einem zweiten Energiewandler 34 zuzuführen
• • Einen zweiten Energiewandler 34 zur Umwandlung der potentiellen Energie des Arbeitsmittels 51 in technisch nutzbare Energie
• • Zuführungen 40, um das noch unter Dosierdruck stehende Arbeitsmittel 51 vom zweiten Energiewandler 34 wieder dem Wärmetauscher 31 zuzuführen
• • Zuführungen 41 zur Zuführung von unter Dosierdruck stehendem kalten Arbeitsmittel 51 als Gewichtsmedium 60 zum ersten Energiewandler 22

The further developed overall system 12 according to the invention ( 7 ) includes at least the following components:

• • A heat exchanger 31 for transferring the thermal energy of a low-temperature heat source to a pressurized liquid working medium 51 without evaporation of the working medium
• • Thermally insulated feeders 40 to feed the heated working medium 52 to a further developed first energy converter 22
• • At least one first energy converter 22 further developed according to the invention for converting the thermal energy of the working medium 52 into potential energy by realizing the flash evaporation according to the TLC2 process
• • Feeds 40 to feed the resulting working fluid vapor 54 to a vapor liquefaction device 32
• • A vapor liquefaction device 32 for liquefying the vaporized working fluid 54
• • Feeds 40 to feed the working medium 51 remaining liquid in the first energy converter 22, the weight medium 60 and the working medium 51 liquefied again in the steam liquefaction device 32 to a collecting container
• • A collection and buffer tank 33 for combining the liquid working medium liquefied in the steam liquefaction device 32 and the weight medium
• • Feeds 42 to feed the liquid, cold working medium under pressure from the collecting container to a second energy converter 34
• • A second energy converter 34 for converting the potential energy of the working medium 51 into technically usable energy
• • Feeds 40 to feed the working medium 51, still under dosing pressure, from the second energy converter 34 back to the heat exchanger 31
• • Feeds 41 for feeding cold working fluid 51 under dosing pressure as weight medium 60 to the first energy converter 22

• • Absaugvorrichtungen für nicht kondensierbare Gase
• • ggf. Trennvorrichtungen für die Trennung von Arbeitsmittel und Gewichtsmedium
• • Filtersysteme zur Reinigung des Arbeitsmittels von Fremdstoffen (z.B. Abrieb)
• • Meßsensoren und Prozess-Steuerungs- und Regeltechnik
• • Wärmespeicher

Various auxiliary and additional systems are not shown in the illustrations, as their position and function can be solved in many different ways. Auxiliary and additional systems can be, for example:

• • Extraction devices for non-condensable gases
• • if necessary, separating devices for the separation of working medium and weight medium
• • Filter systems for cleaning the working medium from foreign substances (e.g. abrasion)
• • Measuring sensors and process control and regulation technology
• • Heat storage

• • Schritt a: Isobares Erwärmen (3: Pkt.2 - Pkt.3) des unter Dosierdruck stehenden flüssigen Arbeitsmittels aus einer Niedertemperaturwärmequelle ohne Verdampfung des Arbeitsmittels
• • Schritt b: Isentrope Umwandlung (3: Pkt.3 - Pkt.5) der aufgenommenen thermischen Energie in einem ersten Energiewandler 21 oder 22 in potentielle Energie
• • Schritt c: Isobares Kondensieren (3: Pkt.5 - Pkt.1) des verdampften Anteils des Arbeitsmittels
• • Schritt d: Isochore Umwandlung (3: Pkt.1 - Pkt.7) der potentiellen Energie über die Fallhöhe H in statischen Druck
• • Schritt e: Isochore Umwandlung (3: Pkt.7 - Pkt.2) eines Teils des statischen Druckes im zweiten Energiewandler 34 in technisch nutzbare mechanische Energie

In both systems 11 and 12, the thermal energy is converted into technically usable energy according to the TLC2 process (see 3 ) in the process steps:

• • Step a: Isobaric heating ( 3 : Point 2 - Point 3) of the liquid working fluid under dosing pressure from a low-temperature heat source without evaporation of the working fluid
• • Step b: Isentropic conversion ( 3 : Point 3 - Point 5) of the absorbed thermal energy in a first energy converter 21 or 22 into potential energy
• • Step c: Isobaric condensation ( 3 : Point 5 - Point 1) of the evaporated portion of the working fluid
• • Step d: Isochoric conversion ( 3 : Point 1 - Point 7) of the potential energy over the drop height H into static pressure
• • Step e: Isochoric conversion ( 3 : Point 7 - Point 2) of a part of the static pressure in the second energy converter 34 into technically usable mechanical energy

Thermodynamic point 2

The starting point of the energy conversion process is point 2 of the TLC2 process (see 3 , TS and pV diagram) in the lower part of the overall systems 11 and 12 (see 4 and 7 ).

The cold liquid working medium 51 is under pressure and is fed through inlets 40 to the heat exchanger 31 for absorbing thermal energy from the low-temperature heat source and is heated therein without evaporating.

In addition to geothermal energy, ocean heat, solar heat, waste heat from technical processes (e.g. steel and plastics industry), heat from cooling processes (e.g. cold storage, data centers), heat from combustion processes (e.g. waste incineration, biogas) or residual heat from other processes (e.g. chemical industry) can be used as low-temperature heat sources.

Depending on the temperature level and temperature difference between the low-temperature heat source used and the available condensation temperature, all organic and inorganic substances as well as mixtures of substances can be used as working fluids that cover the temperature range from the maximum temperature of the low-temperature heat source to the minimum temperature of the vapor condensation as a liquid without thermal decomposition and without freezing.

When selecting the working fluid, care must be taken to avoid chemical reactions between the working fluid and individual components of the overall system.

Thermodynamic point 3

The heated working fluid 52 emerging from the heat exchanger 31 then flows through thermally insulated feed lines 40 to the first energy converter 21 ( 4 , overall system 11) or the further developed first energy converter 22 ( 7 , overall system 12).

In the further developed overall system 12 ( 7 ), additional cold working fluid flows as a weight medium 60 through inlets 41 to the further developed first energy converter 22.

Thermodynamic points 4' and 4"

In the first energy converter 21 ( 4 , overall system 11) or the further developed first energy converter 22 ( 7 , overall system 12), the absorbed thermal energy of the warm liquid working medium 52 is converted into heat according to the TLC2 process (see 3 , points 4' and 4") is converted into potential energy by performing volume change work in the form of lifting work. The working medium and the weight medium (the latter only the entire system 12) are lifted from the lower to the upper area.

Thermodynamic point 5

In the upper part of the first energy converter 21 or 22, the working medium is in accordance with the TLC2 process (see 3 : Course points 4' and 4") partially evaporated and overall cooled.

The still liquid part of the cold working fluid 51 leaves at the upper level (point 5) in the overall system 11 ( 4 ) or total system 12 ( 7 ) the first energy converter 21 or 22 and flows to the collecting container 33.

In the further developed overall system 12 ( 7 ), the weight medium 60 also flows directly to the collecting container 33 and increases the volume of the liquid cold working medium 51.

Thermodynamic point 6

The evaporated and cooled portion of the working medium 54 also leaves the first energy converter 21 or 22 in both overall systems 11 and 12, flows to the vapor liquefaction device 32 and is liquefied again here with a reduction in entropy (point 6). Any non-condensable gases that may have formed are extracted here.

The cold working fluid 51, which has become liquid again, also flows into the collecting tank 33.

Thermodynamic point 1

When the liquid, cold working fluid enters the collecting tank 33, point 1 of the TLC2 process is reached in both overall systems 11 and 12.

The previously absorbed thermal energy is converted, the cold working medium 51 (including the former weight medium 60) now has potential energy.

Thermodynamic point 7

In order to convert the potential energy into technically usable energy, the cold working medium 51 - in the overall system 12 also the weight medium 60 - flows through pressure-stable feed lines 42 to the second energy converter 34 under pressure build-up.

At the entrance of the second energy converter 34, the liquid column generates a high pressure (point 7). This pressure is partially converted into mechanical energy in the second energy converter 34, which can then be converted into electrical energy in a generator, for example, but can also be used as mechanical energy to drive machines.

Thermodynamic point 2

The cold working medium 51 leaves the second energy converter 34 under a residual pressure, hereinafter referred to as the dosing pressure pD. This dosing pressure pD corresponds to point 2 of the TLC2 process and is so high that the working medium 51 does not subsequently begin to evaporate when thermal energy is absorbed again in the heat exchanger 31.

In the overall system 11, the entire working fluid 51 is fed again to the heat exchanger 31.

In the overall system 12, a portion of the cold heat medium 51 is separated as a weight medium 60 and fed directly to the first energy converter 22. The remaining working medium 51 is fed again to the heat exchanger 31.

This marks the starting point of the energy conversion process and closes the cycle.

Comparison of the overall systems 11 and 12

When comparing the pV diagrams of the complete systems 11 and 12 ( 4 and 7 ) it can be seen that in the overall system 12 the greater part of the technically usable energy is obtained from the volume of the working medium 51 with a significantly reduced pressure difference between the points 7 and 2. In accordance with the volume of the weight medium 60 used, the height of the first energy converter 22 is reduced (in comparison to the first energy converter 21), which is represented as a reduced pressure difference between the points 7 and 2 of the pV diagram of the overall system 12 (in comparison to the overall system 11).

However, with the same amount of thermal energy supplied, the overall systems 11 and 12 always generate the same amount of technically usable energy.

performance increase

To increase the performance of the overall systems 11 and 12, several first energy converters 21 or further developed first energy converters 22 can be used in parallel (see 6 - shown using the example of the entire system 11). The number of first energy converters can be as high as desired. A corresponding adjustment of the performance of the jointly used components heat exchanger 31, steam condenser 32, collecting tank 33 and the second energy converter 34 is assumed.

By switching off individual first energy converters 21 or 22 by stopping the supply of working fluid, it is possible to easily adapt the output of the first energy converters 21 or 22 to the amount of available thermal energy. The use of several energy converters 34 that can be switched off individually is advantageous in this case.

Usable temperature range

The operation of the entire systems 11 and 12 is based only on the pressure difference between the vapor pressure at maximum working temperature and the vapor pressure at vapor condensation temperature. The entire system 11 is particularly advantageous for small temperature differences, the entire system 12 for larger temperature differences.

In particular, the fact that the further developed overall system 12 can be operated like an overall system 11 by means of appropriate control means significantly expands the application area of the overall system 12.

Further use of condensation heat

Due to the wide usable and variable temperature range, further use of the condensation heat is also possible if the low-temperature heat source has the appropriate temperature.

For example, at a maximum operating temperature of 150°C and a condensation temperature of 70°C, the condensation heat can heat heating water.

The amount of energy generated by the overall system decreases accordingly. The exergetic efficiency of the overall system changes according to the degree of use of the condensation heat.

Description of the overall systems 13 and 14 for converting thermal energy into technically usable energy as special versions of the overall systems 11 and 12

Depending on the type of low-temperature heat source and the location where the low-temperature heat is provided, special designs of the overall systems 11 and 12 are possible.

In 10 (Overall system 13) and 11 (Overall system 14) shows a preferred arrangement for the use of low-temperature heat from solar thermal heating, but also from flue gases or coolant vapors.

Overall system 13 is a further development of overall system 11. Overall system 14 is a further development of overall system 12.

A common feature of the overall systems 13 and 14 is that the heat exchanger 31 for introducing the low-temperature heat is arranged between the collecting tank 33 and the second energy converter 34 and extends over the fall height H.

The working medium 51 to be heated passes through the heat exchanger 31 while simultaneously building up pressure and is fed to the second energy converter 34 as already heated working medium 52. After the warm working medium exits the second energy converter 34, no evaporation occurs due to the remaining high dosing pressure pD. The heated working medium is then fed directly to the first energy converter 21 or 22.

In 9 The modified two-stage tri-lateral cycle process (hereinafter referred to as M-TLC2) used in overall systems 13 and 14 is shown. Point 2 of the original TLC2 process according to 3 is deleted and point 7 receives a changed position in the new M-TLC2 process.

• • Schritt a: Isentrope Umwandlung (3: Pkt. 4' und 4") der thermischen Energie des erwärmten Arbeitsmittels in einem ersten Energiewandler 21 oder 22 in potentielle Energie
• • Schritt b: Isobares Kondensieren (3: Pkt.5 - Pkt.1) des verdampften Anteils des Arbeitsmittels
• • Schritt c: Isochores Erwärmen (3: Pkt.1 - Pkt.7) des flüssigen Arbeitsmittels bei gleichzeitigem Aufbau von statischem Druck über die Fallhöhe H aus einer Niedertemperaturwärmequelle ohne Verdampfung des Arbeitsmittels
• • Schritt d: Isochore Umwandlung (3: Pkt.7 - Pkt.3) eines Teils des statischen Druckes im zweiten Energiewandler 34 in technisch nutzbare mechanische Energie

The conversion of thermal energy into technically usable energy takes place in the M-TLC2 process in the following process steps:

• • Step a: Isentropic conversion ( 3 : Points 4' and 4") of the thermal energy of the heated working medium in a first energy converter 21 or 22 into potential energy
• • Step b: Isobaric condensation ( 3 : Point 5 - Point 1) of the evaporated portion of the working fluid
• • Step c: Isochoric heating ( 3 : Point 1 - Point 7) of the liquid working fluid with simultaneous build-up of static pressure over the drop height H from a low-temperature heat source without evaporation of the working fluid
• • Step d: Isochoric conversion ( 3 : Point 7 - Point 3) of a part of the static pressure in the second energy converter 34 into technically usable mechanical energy

The thermodynamic course of the M-TLC2 process appears visually similar in the p-V diagram; little changes compared to the TLC2 process.

The situation is different in the T-S diagram, where the missing point 2 and the changed position of point 7 represent the new arrangement of the heat exchanger and the resulting changed course.

For a better understanding, the 10 and 11 the TS diagram and the pV diagram of the respective overall process are shown. The hatched area in the pV diagram corresponds to the thermal energy converted into technically usable work and is the same size for both overall systems with the same input parameters.

Detailed description of the function of the first energy converter 21 or the further developed first energy converter 22 for converting thermal energy into potential energy

The following description presents the operation of the first energy converter 21 ( 12 ) and the further developed first energy converter 22 ( 13 ). Differences are discussed in the text. The physical and technical principles have already been explained in 5 and 6 The following description follows the course of the TLC2 process according to 3 or the M-TLC2 process according to 9 between points 3 and 5.

• • Ein geschlossenes, thermisch isoliertes, aufwärts gerichtetes Rohrsystem mit einem Aufstiegsrohr 130 und einem Abstiegsrohr 160 verbunden durch einen unteren Rohrbogen 110 und einen oberen Rohrbogen 140
• • Eine große Anzahl von in dem Rohrsystem frei umlaufende, mit einer Dichtung versehene, nicht kippende Kolben 170, die die Räume oberhalb und unterhalb des Kolbens voneinander trennen sowie im Abstiegsrohr 160 einen Kolbenstapel 171 bilden
• • Einbringöffnungen im Rohrsystem und einer Einbringvorrichtung 121 im unteren Bereich des Energiewandlers zum Einbringen von warmen Arbeitsmittel 52
• • Auslassöffnungen im Rohrsystem und einer Separierungsvorrichtung 150 im oberen Bereich des Rohrsystems zum Auslassen des flüssigen und verdampften Arbeitsmittels 51 und 54

The first energy converter 21 according to the invention ( 12 ) for the isentropic conversion of thermal energy of a pressurised, heated liquid working medium into potential energy by realising partial flash evaporation according to the TLC process comprises at least the following components:

• • A closed, thermally insulated, upward pipe system with an ascent pipe 130 and a descent pipe 160 connected by a lower pipe bend 110 and an upper pipe bend 140
• • A large number of freely rotating, sealed, non-tilting pistons 170 in the pipe system, which separate the spaces above and below the piston and form a piston stack 171 in the descent pipe 160
• • Inlet openings in the pipe system and an insertion device 121 in the lower part of the energy converter for the introduction of warm working fluid 52
• • Outlet openings in the pipe system and a separating device 150 in the upper part of the pipe system for discharging the liquid and vaporized working medium 51 and 54

• • eine erweiterte Einbringvorrichtung 122 auf dem unteren Niveau des Rohrsystems zum zusätzlichen Einbringen von Gewichtsmedium 60

The further developed first energy converter 22 according to the invention ( 13 ) comprises the same components as the first energy converter 21 plus:

• • an extended introduction device 122 at the lower level of the pipe system for additional introduction of weight medium 60

• • Startvorrichtung zur initialen Inbetriebsetzung des Prozesses
• • Serviceeinrichtungen zum Befüllen des Energiewandlers mit Kolben und Arbeitsmittel, Austausch defekter Kolben oder Reinigung des Arbeitsmittels (z.B. Abrieb)
• • Meßsensoren sowie Prozesssteuerungs- und Regeltechnik
• • Wärmespeicher

Various auxiliary and additional systems are not shown in the illustrations, as their position and function can be solved in many different ways. Auxiliary and additional systems can be, for example:

• • Starting device for initial commissioning of the process
• • Service facilities for filling the energy converter with pistons and working fluid, replacing defective pistons or cleaning the working fluid (e.g. abrasion)
• • Measuring sensors and process control and regulation technology
• • Heat storage

Step 1 - Inserting the media

The starting point for the conversion of thermal energy into potential energy is in the lower part of the pipe system, as shown in the example in the lower pipe bend 110.

From the descent pipe 160, pistons 170, which are under the pressure pK of the subsequent piston stack 171, are introduced into the introduction devices 121 ( 12 ) or 122 ( 13 ). The pressure pK of the piston stack 171 from the descent pipe 160 is greater than the maximum working pressure pA.

The heated working medium 52, which is under a dosing pressure pD - which is greater than the maximum working pressure pA - is supplied from the outside to the introduction device 121 or 122.

The heated working medium 52 is then introduced between two pistons 170 in the introduction device 121 or 122. This area thus becomes a working area AB.

In addition, in the insertion device 122 ( 13 ) of the further developed first energy converter 22, cold working fluid is introduced as a weight medium 60 between two working areas AB. An area filled with weight medium 60 thus becomes a weight area GB.

The amount of media supplied and the time of introduction are controlled by dosing devices 126.

To safely introduce the working medium or the weight medium, individual pistons 170 in the introduction devices 121 and 122 can be briefly stopped by a piston stop device 125. After the stopped pistons 170 are released, the introduced areas are pushed into the riser tube 130 by the pressure of the subsequent pistons 170 or the next introduced areas.

The pistons 170 create a spatial and thermally insulated separation for the heated working medium or the weight medium from the preceding or following areas.

In principle, it is not necessary to give the areas between two pistons a specific assignment to a working area or weight range for the further developed first energy converter 22. Any area between two pistons can be a working area or weight range.

From a technical point of view, however, it may make sense to design the pistons differently and thus specify explicit working and weight ranges between the pistons.

Possible reasons include:

• • The simplified, separate introduction of working medium 52 and weight medium 60
• • Better control options for the energy converter

Step 2 - Conversion of thermal energy into potential energy

After the working areas AB or weight areas GB (the latter only in the further developed first energy converter 22) enter the ascent tube 130, as described in connection with 5 and 6 explained, a slow reduction of the working pressure pA acting on the upper piston. The preferred design of the riser tube 130 according to the invention is vertical without a change in direction. The general basic principle of pressure build-up also allows an oblique, screw-shaped or other upwardly directed design of the riser tube 130.

After falling below a working pressure pA, which depends on the temperature and the vapor pressure curve of the warm working fluid, the working fluid 52 begins to evaporate in a flash vaporization, so that warm working fluid vapor 53 is formed. This leads to an increase in volume of the working area while the working fluid cools down at the same time. This increase in volume causes all working or weight areas in the riser pipe above this working area (the latter only in the further developed first energy converter 22) to be raised.

If the volume increase is sufficiently large, this leads to the escape of cold working medium vapor 54, cold working medium 51 and, in the further developed first energy converter 22, also weight medium 60 in the upper region of the pipe system - shown as an example in the upper pipe bend 140 - into the separation device 150.

As the media exits into the separation device 150, the working pressure pA that is applied to the working and weight areas remaining in the riser tube 130 (the latter only in the further developed first energy converter 22) is reduced. This leads to further expansion evaporation of the still liquid warm working medium 52 in the working areas AB still in the riser tube 130, an expansion of the already existing warm, pressurized working medium vapor 53, an associated increase in the volume of the working areas and the raising of all areas located above an individual working area.

• • Austritt von Medien im oberen Bereich des Rohrsystems
• • einer dadurch initiierten Druckverringerung im Aufstiegsrohr 130
• • einer nachfolgenden Entspannungsverdampfung von warmen Arbeitsmittel 52
• • Ausdehnen des bereits vorhandenen warmen Arbeitsmitteldampfes 53
• • Anheben der Bereiche im Aufstiegsrohr 130

wiederholt sich stetig durch Zuführung neuer Bereiche in den Einbringvorrichtungen 121 bzw. 122. Dadurch unterliegt das warme Arbeitsmittel 52 während des Aufstiegs im Aufstiegsrohr 130 einer kontinuierlichen Entspannungsverdampfung bei gleichzeitiger Abkühlung von flüssigem Arbeitsmittel 52 und dem bereits entstandenen Arbeitsmitteldampf 53.The described process of

• • Leakage of media in the upper part of the pipe system
• • a resulting pressure reduction in the riser tube 130
• • a subsequent flash evaporation of warm working fluid 52
• • Expansion of the already existing warm working fluid steam 53
• • Raising the areas in the riser tube 130

is repeated continuously by supplying new areas in the introduction devices 121 and 122. As a result, the warm working medium 52 is subjected to continuous flash evaporation during the rise in the riser tube 130 with simultaneous cooling of the liquid working medium 52 and the already formed working medium vapor 53.

At the end of the ascent, the working medium 52 has partially evaporated and cooled down to condensation temperature. The resulting working medium vapor 54 is expanded while increasing in volume and cooling down to condensation pressure.

Due to the principle of the freely movable pistons 170, there is no mechanically predetermined pV characteristic curve of the first (21) and the further developed first energy converter (22). This means that the pV characteristic curve of the first energy converter is variable and automatically adapts to the pV evaporation characteristic curve of the working medium in the temperature range used due to the self-regulating working pressure pA of each individual working area and the resulting forced expansion evaporation of the working medium.

Something comparable is not possible with state-of-the-art devices.

• • eine stufenlose Volumenvergrößerung von mehr als 1:100 - bezogen auf das Ausgangsvolumen des flüssigen warmen Arbeitsmittels zum Endvolumen des teilverdampften gasförmigen/flüssigen kalten Arbeitsmittels - sowie
• • eine stufenlose Druckentspannung von weit mehr als 1:10 - bezogen auf den maximalen Arbeitsdruck auf dem unteren Niveau zum minimalem Arbeitsdruck auf dem oberen Niveau - möglich

Likewise,

• • a continuous volume increase of more than 1:100 - based on the initial volume of the liquid warm working medium to the final volume of the partially evaporated gaseous/liquid cold working medium - and
• • a continuous pressure relief of far more than 1:10 - based on the maximum working pressure at the lower level to the minimum working pressure at the upper level - is possible

Step 3 - Separation and application of media

After the working medium vapor 54, the cooled, liquid working medium 51 or weight medium 60 (the latter only in the further developed first energy converter 22) emerge from the pipe system in the upper pipe bend 140, the media are separated in the separation device 150. The liquid working medium 51 is caught, collected and fed to the collection container 33. In the further developed energy converter 22, the liquid working medium 51 is caught together with the weight medium 60.

The working medium vapor 54 is fed to the vapor liquefaction device 32 through corresponding feeds 40. Any working medium droplets entrained by the working medium vapor are separated in the separation device 150 and fed to the collecting container 33.

Step 4 - Returning the pistons

The pistons 170, which are no longer functional after the media have exited the pipe system, are guided further to the downpipe 160. There, the weight of the pistons forces the remaining working medium vapor 54 out of the pipe system into the separation device 150 through the outlet openings provided for this purpose.

The pistons 170 are brought together as a piston stack 171 and, due to their own weight, generate the piston pressure pK required in the introduction devices 121 and 122.

The inventive design of the first energy converters 21 and 22 as a closed pipe system with free-running pistons opens up the possibility of energy conversion from thermal into potential energy with a very large and variable working range with regard to the possible volume increase and the working pressure to be reduced.

The stepless and variable flash evaporation of a working medium, which can be achieved through the principle of individual small working areas, can only be compared with a very finely stepped turbine.

The particular advantage of the large number of individual working areas is the associated long time (compared to the state of the art) from the start of the flash evaporation of the working medium to the exit at the upper level (see 3 , point 3-5 of the TS diagram).

With a maximum number of 5 newly supplied working areas per second (ideally less than one working area per second) and a number of at least 10 working areas required to build up pressure in the pipe, a relatively long time of flash evaporation of 2-10 seconds results (at higher temperatures of the warm working medium 52 due to the larger number of working areas up to several minutes), which is not achievable with devices according to the state of the art.

This long flash evaporation time prevents explosive vapor bubble formation, which poses a great danger in state-of-the-art devices due to droplet erosion.

As a further advantage, the flash evaporation curve in the TS diagram can be 3 and 9 from point 3 to point 5 must be completed safely and completely and the absorbed thermal energy must be fully converted.

In 14 In addition, various scenarios are shown as TS diagrams.

14a - Course under basic operating conditions defined by the temperature of the heat source and the vapor condensation temperature

14b - Course with increased temperature of the heat source compared to the basic operating conditions (e.g. use of solar thermal energy as a heat source in summer)
The starting point of the flash evaporation (point 3) is shifted upwards.
More thermal energy is converted than under basic operating conditions.

14c - Course with increased vapor condensation temperature compared to the basic operating conditions
(Example: use of geothermal energy as a heat source and cooling by ambient air in summer) The condensation line from point 5 to point 1 is shifted upwards.
The relaxation curve from point 3 to point 5 is shortened.
Less energy is converted than under basic operating conditions.

14d - Course with increased heat source temperature and increased vapor condensation temperature compared to the basic operating conditions
(Example: use of solar thermal energy as a heat source and cooling by ambient air in summer)
Depending on the temperature difference between points 2 and 3, more or less thermal energy is converted than under basic operating conditions.

Another important point is the design of the circumferential pipe system and the pistons.

The tubes for guiding the pistons are provided with a good sliding thermal internal insulation such as PTFE or polyamide (PA).

The pistons themselves are provided with a sealing and sliding material on the sealing surfaces that matches the material of the inner insulation of the tube, which ensures both sealing of the areas and thermal insulation.

Within a working area, the contact of the working fluid with the pipe wall and the piston scraping the working fluid off the pipe wall result in turbulence and intensive mixing of the working fluid. This promotes the evaporation of the working fluid.

This turbulence can be further promoted by a suitable design of the piston and the piston seal.

The pistons also preferably have a roughened, porous surface, which promotes the formation of bubbles when the working medium evaporates (comparable to the effect of boiling stones).

Since the inventive design means that only very small pressure differences of less than 0.001 MPa (0.01 bar) occur on the pistons (pressure difference = piston weight/area), the main task of the piston seal is to provide a supporting function to prevent the pistons from tipping over in the pipe system. This is possible with a suitable piston design. Corresponding piston designs are known to those skilled in the art.

The tube cross-section is a supportive factor in the piston design. In addition to a circular cross-section, non-circular tube cross-sections (e.g. ellipse or oval) have advantages, for example, in the design of the insertion device or the outlet openings and other tasks.

A design of the lower and upper sections of the circulating pipe system as a horizontal zone with constant pressure (examples see 15 ) in combination with a non-circular pipe cross-section facilitates the technical design of the introduction device 120 and the separation device 150.

Process examples

As shown in Table 1, the overall system can be used to 4 Even small temperature differences of 10°K can be utilized.

The thermodynamically given low pressure difference of only 0.033 MPa (0.33 bar) between the maximum working pressure and the vapor condensation pressure in the first energy converter 21 according to the invention due to the temperature difference is converted into a technically usable pressure difference of 0.25 MPa (2.5 bar) for the second energy converter 34.

Something comparable cannot be achieved with state-of-the-art devices.

The inventive use of the further developed energy converter 22 according to 13 with additional weight ranges at higher inlet temperatures reduces the technically necessary height to build up the maximum working pressure pA between the lower and upper levels, as already explained in the explanation of 6 and 7 shown.

Table 2 shows an example comparison of the overall systems 11 (without weight medium) and 12 (with weight medium) with otherwise identical input parameters.

As can be seen from the values, when using a weight medium (see 7 ) a significantly lower height of the upward-leading pipe is required to build up the required working pressure. The technically minimum required differential pressure for the second energy converter 34 (in the example 0.3 MPa) thus becomes the determining factor for the amount of weight medium used and the height of the first energy converter.

Table 3 shows examples of the operating parameters of an overall system 12 with a further developed first energy converter 22 at different operating temperatures.

The temperature scenario shown (increase in the maximum operating temperature from 40 to 100 °C) corresponds to the daily course of an energy converter with solar thermal heat supply and liquefaction of the working medium vapor by ambient air with increasing ambient temperature (increase in the condensation temperature from 20 to 40 °C).

The changing operating parameters are clearly visible depending on the change in the maximum working temperature and the condensation temperature. The last column shows an example of the influence of the condensation temperature on the achievable performance.

Assuming a number of newly added working areas per second, the number of working areas used corresponds to the number of seconds in which the working medium passes through the flash evaporation curve from thermodynamic point 3 to point 5 of the TLC2 process. Table 1 Process example for the implementation of the TLC2 process in overall system 11 with a temperature difference of 10° between the inlet and condensation temperatures Input parameters Unit Overall system 11 Max. working temperature °C 40 Condensation temperature °C 30 Average efficiency according to Carnot % -1.6 Working fluid / density - / kg/m2 n - Pentane / 605.76 Max. working pressure MPa 0.115 Condensation pressure MPa 0.082 Quantity of work equipment kg 1.6 Pipe diameter m 0.1 Starting height of work equipment m 0.33 Result parameters Quantity of working fluid, evaporated / liquid kg 0.1 / 1.5 Final height of working fluid, liquid + steam m 5.54 Relaxation ratio 1:16.9 Required pipe height m 48 Number of work areas - 19 Differential pressure between point 7 and 2 MPa 0.25 Work performed per work area kW 0.66 Area performance kW/ ^m2 84.5 Table 2 Comparison of the complete systems 11 and 12 at an inlet temperature of 100°C and a condensation temperature of 40°C Input parameters Unit Overall system 11 Total system 12 Max. working temperature °C 100 Condensation temperature °C 40 Average efficiency according to Carnot % 8.74 Working fluid / density - / kg/m2 n - Pentane / 605.76 Max. working pressure MPa 0.59 Condensation pressure MPa 0.115 Pipe diameter m 0.1 Amount of heated working fluid kg 0.23 Starting height of work equipment m 0.0515 Amount of cold n-pentane as weight medium kg 0 5.6 Result parameters Quantity of working fluid, evaporated / liquid kg 0.1 / 0.13 Final height of working fluid, liquid + steam m 3.5 Relaxation ratio 1:68 Required pipe height m 1525 138 Number of work areas - 1564 63 Differential pressure between point 7 and 2 MPa 8.6 0.3 Usable work equipment per work area (+weight range) kg 0.23 5.83 Work performed per work area kW -3.15 Area performance kW/ ^m2 -400 Table 3 Example spread of working parameters for solar thermal heating and cooling by ambient air Input parameters Unit Total system 12 Operating mode of first energy converter - Energy converter 22 Max. working temperature °C 40 60 80 100 100 Condensation temperature °C 20 30 40 20 Average efficiency according to Carnot % 3.3 4.7 6 8.74 12 Working fluid / Density @20°C - / kg/m2 N - Pentane / 625.76 Max. working pressure MPa 0.115 0.214 0.368 0.59 Condensation pressure MPa 0.056 0.082 0.115 0.056 Pipe height m 138 Pipe diameter m 0.1 Amount of warm working fluid kg 0.79 0.5 0.355 0.23 0.185 Starting height of work equipment m 0.16 0.1 0.077 0.051 0.041 Amount of cold weight medium kg 1.6 2.8 3.45 5.6 10 Height Weight Medium m 0.326 0.58 0.73 1.18 2 Result parameters Working fluid, evaporated / liquid kg 0.1 / 0.69 0.1 / 0.4 0.1 / 0.25 0.1 / 0.13 0.1 / 0.08 Final height of working fluid (liquid + steam) m 7.5 5.3 3,825 3.80 7.4 Relaxation ratio 1:47 1:53 1:50 1:74 1:170 Number of effective work areas - 18 30 49 63 41 Differential pressure between point 7 and 2 MPa 0.3 Usable tool kg 2.39 3.2 3.8 5.83 10.2 Work performed per work area kW 1.23 1.77 2.25 3.33 4.9 Area performance at a working area / sec kW/ ^m2 156 225 286 424 629

Claims (29)

Energy converter (21) for the isentropic conversion of the thermal energy of a pressurized liquid working medium (52) heated by contact with a heat source into potential energy by realizing a partial flash evaporation according to the TLC2 process , characterized by at least the following components: • A closed, thermally insulated, upwardly directed pipe system with an ascent pipe (130) and a descent pipe (160), connected by pipe bends (110, 140) • A number of at least 10 pistons (170) rotating freely in the closed pipe system • The pipes for guiding the pistons (170) are provided with a good sliding thermal inner insulation such as PTFE or polyamide (PA) • The pistons (170) are provided on the sealing surfaces with a sealing and sliding material that matches the material of the inner insulation of the pipe and ensures both sealing of the areas and thermal insulation • Introduction openings and an introduction device (121) on the lower level of the pipe system for introducing a working medium (52) heated by contact with a heat source into a working area (AB) between two pistons (170) • Outlet openings in the casing of the pipe at the upper level for discharging the remaining liquid (51) and the evaporated (54) working medium from the pipe system • A separation device (150) for separating the evaporated working medium (54) from the liquid, cold working medium (51). Energy converter (22) to Claim 1 characterized by at least the following components: • Additional introduction openings and an introduction device (122) on the lower level of the pipe system for introducing a weight medium (60) into a weight area (GB) between two working areas (AB), wherein the weight medium (60) has not been heated by the heat source • Outlet openings on the upper level for the joint discharge of the remaining liquid (51) and the evaporated (54) working medium as well as the weight medium (60) from the pipe system • A separation device (150) for separating the evaporated working medium (54) from the remaining liquid, cold working medium (51) as well as the liquid weight medium (60). Energy converter according to one of the preceding claims, characterized in that the pipe system is dimensioned such that at least 10, preferably more than 20 independent, individual working areas (AB) are provided for converting the thermal energy of the heated working medium (52) into potential energy in the riser pipe (130) of the energy converter. Energy converter according to one of the preceding claims, characterized in that the pipe system is dimensioned such that the movement of an individual working area (AB) from introduction at the lower level to reaching the upper level takes at least 2 seconds, preferably more than 10 seconds. Energy converter according to one of the preceding claims, characterized in that there are pressure differences of less than 0.001 MPa at the seal of the pistons (170) between the individual working areas (AB) or working areas (AB) and weight areas (GB). Energy converter according to one of the preceding claims, characterized in that the pistons (170) have a roughened, porous surface which promotes bubble formation of the working medium. Energy converter according to one of the preceding claims, characterized in that the relaxation of the working pressure (pA) of the working areas (AB) takes place continuously. Energy converter according to one of the preceding claims, characterized in that the volume increase of the working areas (AB) takes place continuously. Device for converting the thermal energy of a low-temperature heat source with temperatures of maximum 200°C into technically usable mechanical energy, characterized by , • at least one first energy converter according to one of the preceding Claims 1 - 8th , which raises a working medium (AM) from a lower level to an upper level using thermal energy from a low-temperature heat source with a maximum temperature of 200°C by implementing flash evaporation according to the TLC2 process and converts the thermal energy absorbed by the working medium (AM) into potential energy of the working medium (AM) • a second energy converter (34) which releases the gained potential energy as technically usable mechanical energy by returning the working medium (AM) from the upper to the lower level. Device (11) according to Claim 9 , characterized in that it comprises at least the following components: • A heat exchanger (31) for transferring the thermal energy of a low-temperature heat source with temperatures of maximum 200°C to a liquid working medium (51) under dosing pressure (pD) without evaporation of the working medium • Thermally insulated feeds (40) for feeding the heated working medium (52) to a first energy converter (21) according to one of the Claims 1 until 8th • At least one first energy converter (21) after one of the Claims 1 until 8th for converting the thermal energy of the working medium (52) into potential energy • Feeds (40) to feed the working medium (51) remaining liquid in the first energy converter (21) to a collection and buffer tank (33) • Feeds (40) to feed the working medium (54) evaporated in the first energy converter (21) to a vapor liquefaction device (32) • A vapor liquefaction device (32) for liquefying the evaporated working medium (54) • Feeds (40) to feed the liquefied working fluid (51) to a collection and buffer tank (33) • A collection and buffer tank (33) for bringing together the working fluid (51) that remained liquid in the first energy converter (21) and that liquefied in the vapor liquefaction device (32) • Feeds (40) to feed the liquid, cold working fluid (51) from the collection tank (33) to a second energy converter (34) while building up static pressure • A second energy converter (34) for converting the potential energy of the working fluid (51) into technically usable energy • Feeds (40) to feed the working fluid (51) that is still under dosing pressure (pD) from the second energy converter (34) back to the heat exchanger (31). Device (13) according to the Claim 9 , characterized in that it comprises at least the following components: • At least one first energy converter (21) according to one of the Claims 1 until 8th for converting the thermal energy of a heated working medium (52) under metering pressure (pD) into potential energy • Feeds (40) to feed the working medium (51) that has remained liquid in the first energy converter (21) to a collection and buffer tank (33) • Feeds (40) to feed the working medium (54) that has evaporated in the first energy converter (21) to a steam liquefaction device (32) • A steam liquefaction device (32) for liquefying the evaporated working medium (54) • A collection and buffer tank (33) for combining the working medium (51) that has remained liquid and that liquefied in the steam liquefaction device (32) • Feeds (42) to feed the working medium (51) from the collection and buffer tank (33) to a heat exchanger (31) • A heat exchanger (31) for transferring the thermal energy of a low-temperature heat source to a liquid working medium (51) without Evaporation of the working fluid while simultaneously building up a high static pressure • Thermally insulated feeds (42) to feed the liquid, heated and highly pressurized working fluid (52) from the heat exchanger (31) to a second energy converter (34) • A second energy converter (34) to convert potential energy of the heated working fluid (52) into technically usable energy • Thermally insulated feeds (40) to feed the heated working fluid (52) to the first energy converter (21). Device (12,14) according to one of the Claims 9 until 11 , characterized in that in addition to the working medium (AM) a weight medium (60) is raised from the lower to the upper level. Device (12,14) according to one of the Claims 9 until 12 characterized in that the device comprises technical means for providing unheated working medium (AM) as a weight medium (GM). Device (11-14) according to one of the Claims 9 - 13 , characterized in that several of the first energy converters (21,22) according to one of the Claims 1 until 8th arranged in parallel, which share the other components listed. Device (11-14) according to Claim 14 , characterized in that the plurality of first energy converters (21,22) can be individually switched on or off. Device (11-14) according to Claim 15 , characterized in that it comprises a control and regulation system which controls the number of first energy converters (21, 22) switched on or off and adapts them to changes in the temperature of the low-temperature heat source, the condensation temperature or the available amount of energy of the low-temperature heat source. Device (11-14) according to one of the Claims 9 - 16 , characterized in that it comprises a control and regulation system which regulates the quantity of heated working medium (52) and optionally of the weight medium (60) fed in and adapts it to changes in the temperature of the low-temperature heat source, the condensation temperature or the available energy quantity of the low-temperature heat source. Method for converting the thermal energy of a working medium (52) heated by the thermal energy of a low-temperature heat source with a temperature of maximum 200°C into potential energy of the working medium, comprising the steps • The warm, liquid working medium (52) is fed into an energy converter (21,22) according to one of the Claims 1 - 8th introduced • The warm, liquid working fluid (52) is guided in the energy converter (21,22) in a spatially delimited working area (AB) • The working areas (AB) with the warm, liquid working fluid (52) are raised from a lower level to an upper level in the energy converter (21,22), whereby the raising of the working fluid (52) to the upper level takes place by isentropic conversion of the thermal energy of the working fluid (52) into lifting work by a partial flash evaporation of the working fluid (52) according to the TLC2 process. Procedure according to Claim 18 , characterized in that in addition to the heated working medium (52) a non-heated weight medium (60) is raised from the lower to the upper level. Procedure according to Claim 19 , characterized in that the weight medium (60) is transported to the upper level in spatially defined weight areas (GB) in a thermally insulated manner from the heated working medium (52). Method according to one of the above Claims 18 - 20 , characterized in that the conversion of the thermal energy of the working medium (52) into potential energy in the energy converter (21, 22) takes place in at least 10, preferably more than 20 independent, individual working areas (AB). Method according to one of the above Claims 18 - 21 , characterized in that the conversion of the thermal energy of the working medium (52) into potential energy in the energy converter (21,22) takes place continuously and steplessly. Method according to one of the above Claims 18 - 22 , characterized in that an automatic adaptation of the pV characteristic curve of the device to the pV evaporation characteristic curve of the working medium used takes place. Method for converting the thermal energy of a low-temperature heat source with a maximum temperature of 200°C in a closed circuit into technically usable mechanical energy, characterized in that the conversion takes place in at least the following steps: • the thermal energy of the low-temperature heat source is converted in a first step in a method according to the Claims 18 - 23 converted into potential energy • the potential energy is converted in a second step into technically usable mechanical energy. Procedure according to Claim 24 with at least the following process steps: • Step a: Isobaric heating of a liquid working medium (51) under dosing pressure (pD) from a low-temperature heat source without evaporation of the working medium • Step b: Isentropic conversion of the absorbed thermal energy in at least one, preferably several first energy converters (21,22) according to Claim 1 - 8th into potential energy of the working fluid • Step c: Isobaric condensation of the evaporated portion of the working fluid (54) • Step d: Isochoric conversion of the potential energy of the working fluid (51) in a second energy converter (34) into technically usable mechanical energy. Procedure according to Claim 24 with at least the following process steps: • Step a: Isentropic conversion of the thermal energy of a heated working medium (52) under dosing pressure in at least one, preferably several first energy converters according to Claim 1 - 8th into potential energy of the working fluid (51) • Step b: Isobaric condensation of the evaporated portion of the working fluid (54) • Step c: Isochoric heating of the liquid working fluid (51) with simultaneous pressure increase from a low-temperature heat source without evaporation of the working fluid (52) • Step d: Isochoric conversion of the potential energy of the working fluid (52) in a second energy converter (34) into technically usable mechanical energy. Method according to one of the Claims 24 - 26 , characterized in that by varying the amount of heated working medium (52) and optionally of the weight medium (60), a continuous adaptation to changes in the temperature of the low-temperature heat source takes place. Method according to one of the Claims 24 - 27 , characterized in that by varying the amount of heated working medium (52) and optionally of the weight medium (60), a continuous adaptation to changes in the condensation temperature takes place. Method according to one of the Claims 24 - 28 , characterized in that by varying the amount of heated working medium (52) and optionally the weight medium (60), a continuous adaptation to changes in the available amount of energy of the low-temperature heat source takes place.

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